1. Field of the Invention
the present invention relates to a curable resin composition comprising a saturated hydrocarbon polymer having at least one silicon-containing group which has at least one hydroxyl or hydrolyzable group bonded to a silicon atom and is crosslinkable through the formation of a siloxane bond (hereinafter referred to as a "reactive silicon-containing group").
2. Description of the Prior Art
It is known that saturated hydrocarbon polymers having at least one reactive silicon-containing group in a molecule have interesting properties that they are crosslinked through the formation of siloxane bonds which is associated with the hydrolysis of reactive silicon-containing groups with moisture even at room temperature, and provide rubbery cured materials. Such polymers are useful as sealing materials for construction or sealing materials for insulating glass units, since they have excellent heat resistance, water resistance, weather resistance and the like.
The sealing materials for construction are required to have good handling properties and workability, since they are applied at construction sites using caulking guns and the like. The sealing materials for insulating glass units are discharged using applicators, that is, apparatuses for discharging sealing materials, in factories for insulating glass units. In this case, good workability with good discharging properties is required for the sealing materials.
However, saturated hydrocarbon polymers such as polyisobutylene have high viscosity and thus low handling properties, when they are used as sealants such as the sealing materials for construction or insulating glass units. Thus, they are plasticized by the addition of hydrogenated polybutene, paraffinic oils, naphthenic oils, and the like. However, the use of such plasticizers may be associated with some problems, for example, large heating loss, insufficient plasticizing effects, low flowability at low temperature, etc. Because of the low flowability at low temperature, the sealing materials for construction, which have to be applied at the construction sites, are attended with low extrudability or workability in winter seasons.